Process for manufacturing iron-oxid castings.



LUDWIG: SGHERBEL, OF BUSSI, AQUILA, ITALY, ASSIGNOR T0 ELETTROCHIMICA, 0F ROME, ITALY.-

PROCESS FOR MANUFACTURING 'IRON-OXID CASTIN GS.

No Drawing.

To all whom it may concern:

Be it known that I, Loowio SoHnRBnL, a subject of the Emperor of Germany, and residing at Bussi, Province of Aquila, Italy, have invented certain new and useful Improvements in Processes for Manufacturing Iron-Oxid Castings, of which the following is a specification. Y

The invention relates to an improved process for manufacturing iron oxid. castings, and has for its object to obtain castings which are rich in ferric oxid by uslng the almost worthless burnt pyrites or other iron oxids, without special regard to purity, or metallic iron itself.

Many methods have been devised for making iron oxid castings depending on the fusion in the electric furnace of iron oxids or the oxidation of metallic iron, with a view to casting articles adapted to resist chemical actions and having a small degree of fragility; they are composed of magnetite or similar bodies.

It is known that when ironoxid is melted, a dissociation of the ferric oxid into ferrous oxid (ZFe O S4FeO 0 occurs near the melting point, so that mixtures are obtained in which the ratio phone with Fe. or by treating the melted oxids with gases containing oxygen, for instance, air, as described in the Italian Patents Nos. 75119 and 75135, granted to the Societa Italiana di Elettrochimica. Other methods comprise processes for obtaining magnetite by burning iron in oxygen or Specification of Letters Patent.

Patented Dec. 7, 1915.

Application filed August 1, 1914. Serial No. 854,570.

' some other oxidizing agent. By these processes, magnetite is obtained which yields castings of higher chemical and mechanical resistance and more easily yielding sound castings. All the known methods however are not easily carried out and they require the use of raw material of high purity, besides careful and costly supervision, while giving, at the best hypothesis, castings having the composition of the magnetic iron oxid which are not sufiiciently resistant to chemical agents.

By my invention, castings are obtained which possess a much higher resistance to chemical and mechanical action and are more easily cast sound, even when using impure raw materialswith even- 1015% and upward of foreign substances. F or this purpose, instead of stopping at magnetite in which the ratio 263 i 7 %FeO is equalto 2.21, oxid mixtures are obtained in which this ratio is higher than 3 until they come near to ferric oxid Fe O I attain this ratio of three and exceed it at will, by oxidizing under pressure the mass of melted oxids with oxygen or gases rich in oxygen (also air), previously heated or not, or by treating the mass with oxygen-carrying agents, and further by strongly stirring the melted mass. The operation must be carried out quickly, so as to-prevent the solidification of the mass which becomes pasty toward 1350 (l, and while operating with a large excess of gas so as to have an excess of pressure such as will prevent the dissociation The castings" must further be cast while injecting oxidizing gas in order to avoid the dissociation also during pouring.

My method is carried out by injecting the oxidizing gas into the mass directly melted in the closed electric furnace, or by socrn'rn ITALIANA IDI pouring the mass from the furnace into a or other suitable means, where the oxidizing gasis injected, or by treating the melted oxids with oxygencarrying agents so that an excess of oxygen is developed. The castings thus obtained species of converter,

are composed nearly exclusively of F6 0,, and they have not, like the, castings of magnetite, a structure with large crystalline grains, but a compact, homogeneous and 5' very fine structure without blisters which produce holes in the cast articles.

position of Fe O These castings are 7 adapted for the most varied uses on account of their good chemical and mechanical qualities. I

v The process may be used for the oxidation not only of ironoxids and of metallic iron,

but-also of mixtures of diflerent oxide as set forth in the Italian Patent No. 75185, such as mixtures of iron oxids with oxids of manganese, tungsten, titanium, chromium,

' Z vanadium, cobalt, inickel, molybdenum,

uranium or the likes What I claim is: 1. The herein described process for manufacturing iron oxid castings composed of mixtures 1n which the ratio is more than 3 and which may attain the composition Fe O ,-by treating a melted iron containing bath with oxygen under pressure and while intimately stirring the mass and then casting the produced oxids in an oxidizing atmosphere. v

2. The process of manufacturing iron oxid castings which consists in treating impure iron oxid with oxygen under pressure and while stirring, and thereinafter castingthe produced oxids in suitable molds.

In testimony whereof I have signed my name in the presence of two subscribing wit nesses the 16th day of July 1914.

- DR. LUDWIG SCHERBEL.

Witnesses:

GIOVANNI VALATELLI,

CORELLO FONTANI. 

